You might first think about sports when you hear the word base, but not all bases are on the baseball diamond. In chemistry, a base is a molecule that reacts with an acid, often by accepting a proton from the acid or from water. Baking soda and dish soap are common bases.
When we encounter the word mole, some of us might think of a small, fuzzy animal that burrows in gardens, or perhaps the common, pigmented marks on our skin. But in chemistry, the mole is a key unit of measurement; its name is derived from the word molecule. Similar to how “dozen” is another way of saying 12, “mole” is another way of saying 602,214,076,000,000,000,000,000 (that’s about 602 billion trillion), specifically for elementary entities such as molecules and atoms. Scientists sometimes abbreviate this number as 6.02 x 1023, which is why Mole Day is celebrated from 6:02 a.m. to 6:02 p.m. on October 23 each year.
You probably think of a rude or offensive remark when you think of the word insult, but to biomedical researchers, an insult is the cause of some kind of injury to the body. Insults can come in a variety of forms, such as an infection or a physical trauma.
The word culture may make you think of a flag, style of clothing, celebration, or some other tradition associated with a particular group of people. But in biomedical science, a culture is a group of cells grown in a lab. Scientists use cultures to learn about basic biological processes and to develop and test new medicines.
Credit: NIGMS.
The Birth of a Culture
Scientists can grow many types of cells as cultures, from bacteria to human cells. To create a culture, a researcher adds cells to a container such as a Petri dish along with a mix of nutrients the cells need to grow and divide. The exact recipe varies depending on the cell type. (Because many lab containers were historically made of glass, researchers sometimes refer to studies that use cultures as in vitro—Latin for “in glass.”) Once the cells multiply and fill their container, researchers split the culture into new containers to produce more.
When you encounter the word expression, you may think of a smile, a grimace, or another look on someone’s face. But when biologists talk about expression, they typically mean the process of gene expression—when the information in a gene directs protein synthesis. Proteins are essential for virtually every process in the human body.
Many of us learned in English class that an antagonist is a person or thing that a hero fights. But in biomedical science, an antagonist is a molecule that binds to a cellular receptor to prevent a response, such as a muscle contraction or hormone release. Antagonists can be important medical treatments, like the antagonist naloxone—also known as
Narcan —that can reverse an opioid overdose.
Credit: NIGMS; Yekaterina Kadyshevskaya, The Scripps Research Institute.
When most of us hear the word tissue, we think of something we reach for when we have a runny nose. But in biology, a tissue is a group of cells that act together to carry out a specific function.
Credit: NIGMS; and Tom Deerinck and Mark Ellisman, NCMIR.
Your body has four basic types of tissues:
Muscle tissue provides movement. Types include voluntary muscles, like those in the arms and legs, and involuntary muscles, such as those that move food through the digestive system.
Nervous tissue carries messages throughout the body and includes the brain, spinal cord, and nerves.
Connective tissue supports other tissues and binds them together. Examples include ligaments, tendons, bones, and fat.
Epithelial tissue creates protective barriers and includes the skin and the linings of internal passageways.
For many people, the word pathway may bring to mind stepping stones in a garden or a trail through a forest. But when biologists talk about a pathway, they’re referring to a series of actions among molecules in a cell that leads to a certain product or change within that cell. Pathways maintain balance during walking, control how the eyes’ pupils respond to light, and affect skin’s reaction to changing temperature. They control our bodies’ responses to the world, and errors in them can lead to disease.
In everyday use, most people understand translation to mean converting words from one language to another. But when biologists talk about translation, they mean the process of making proteins based on the genetic information encoded in messenger RNA (mRNA). Proteins are essential for virtually every process in our bodies, from transporting oxygen to defending against infection, so translation is vital for keeping us alive and healthy.